Yarn carrier stop for flat knitting machines



y 1941- J. J. DOYLE 2,240,985

. YARN CARRIER STOP FOR FLAT KNITTING MACHINES Filed June 9, 1959 2 Sheets-Sheetl WITNESSES: I N VEN TOR:

ATTORNEYS.

May 6, 1941. J. J. DOYLE 2,240,985

YARN CARRIER STOP FOR FLAT KNITTING MACHINES Filed June 9, 1939 2 Sheets-Sheet 2 INVENTOR: John 1.00 Le,

A TTORNEYS.

Patented May 6, 1941 UNITED STATES PATENT OFFICE YARN CARRIER. STOP FOR FLAT KNITTING MACHINES Application June 9, 1939, Serial No. 278,277

9 Claims.

This invention relates to yarn carrier stops for knitting machines, particularly fiat knitting machines of the type ordinarily employed in the production of full fashioned stockings and the like.

Such knitting machines have from eighteen to thirty-six knitting sections, each with its own set of needles upon which a stocking blank is formed, and longitudinally-extending endwisereciprocated rods with feeds by which individual yarns are concurrently fed to the needles of the several sections. The throw of the carrier rods is limited by stops which are usually mounted on shiftable supports so that the width of the fabric may be varied as in fashioning operations, or that reinforced areas of different contours may be formed with splicing or plating yarns as the knitting of the fabric progresses, said rods receiving their movement by virtue of connection to individual friction boxes on a longitudinal friction box rod which has a constant endwise movement in excess of that required for the rods. Due to the length and weight of the carrier rods, they naturally have considerable momentum (which increases with machine speed) and are thus prone to rebound upon being suddenly arrested by the stops notwithstanding the restraint imposed by the friction boxes, with attendant fouling and damaging of the needles and/or sinkers of the machine, the remedying of which is costly, not only from the standpoint of the replacements made necessary, but also from the standpoints of the labor involved and the loss of production by reason of the enforced idling of the machines.

My invention has for its chief aim to prevent contingencies such as above pointed out, which objective I attain in practice as hereinafter more fully disclosed, by incorporating with each stop,

a shock-absorbing element whereof the buffing effect is regulatable to suit the requirements of the particular carrier rod with which it is associated.

Other objects and advantages will appear from the following detailed description of the attached drawings, wherein Fig. I is a broken out fragmentary view in top plan of a fiat knitting machine which is fitted with yarn carrier stops conveniently embodying my invention.

Fig. II shows the rear elevation of the portion of the machine comprehended in Fig. I,

Fig. III is a fragmentary detail view on a larger scale, partly in broken out section and partly in elevation, of one of the yarn carrier rod stops and the carrier rod which it controls.

Fig. IV is a view like Fig. III showing how the movement of the carrier rod is cushioned by the shock-absorbing element of the stop.

Fig. V is an end elevation of the carrier rod stop viewed as indicated by the angled arrows VV in Fig. III.

Fig. VI is a view corresponding to Fig. III and showing an alternative embodiment of my invention; and

Fig. VII is a perspective View showing another modification of my invention.

The knitting machine chosen for convenience of exemplifying my invention and partly shown in Figs. I and II of the drawings, is of the flat Cotton type such as is ordinarily employed in the production of full fashioned stockings and the like, having a plurality of the longitudinallyextending yarn carrier rods 1 which, as a group, are arranged at an angle transversely of the machine, and which are supported for endwise reciprocation in guides 2 suitably connected to the machine 3. As usual, each rod l is fitted with a plurality of yarn laying fingers such as the one shown at 4 in Fig, III, corresponding in number with that of the knitting sections of the machine. The longitudinal friction box rod 5 of the machine is likewise supported for endwise reciprocation in fixed guides on the frame 3, one of such guides being shown at 6, said rod having a fixed throw in excess of the maximum ever required for the carrier rods I, and being actuated in a well known manner by a coulier motion (not illustrated). The rod 5 of course has as many friction boxes as there are carrier rods. Only one of these boxes is shown in the drawings at 1, coupled by means of its retractable latch bolt 8 with the lowermost carrier bar I of the group. Also as usual, the machine is equipped at opposite ends with narrowing heads, whereof one is shown at 9. Mounted on the reversely pitched screw spindle H) of the head 9 are nuts [2 and I2 for controlling the traverse of the narrowing comb rods (not illustrated) of the machinein a well known manner. The single thread spindle l3 of the narrowing head carries the nut M with spaced angularly projecting bracket arms l5 between the ends of which extends an axis pin l6 whereon the end stops I! for the carrier rods I are pivoted. Associated with the narrowing head 9 is a spindle racking mechanism l8 which may also be of well known construction and which need not therefore be described herein. As instanced in Figs. III and IV, each of the end stops I! has a manipulating handle [9 and an adjustable abutment screw 20 with a head 2l against which the end of the corresponding carrier rod l strikes. After common practice, the screw threadedly engages a tapped bore 22 in the pendant lug projection 23 of the stop IT. The abutment screw 20 is fixable against accidental displacement in adjusted positions by a jam nut 24.

In order to retard or decelerate' the movement of the carrier rods I and thereby prevent rebounding thereof when they strike the abutment screws 25), each stop I! is provided in accordance with my invention, with a cushioning or shockabsorbing element in the form of a plunger 25 which normally projects forwardly beyond the abutment screw. As shown, the front orhead' end Zliof the plunger 25 fits a smooth bore 27 in the stop l1, said bore lying above and: parallel to the tapped bore 22 for the abutment screw 20. The diametrically reduced stem 28 of the plunger 25 passes freely through the correspondinglyreduced rearward continuation 29 of the bore 27. Surrounding the stem 28 of the plunger 25 within the bore 2'5 with its ends bearing against the shoulders 30 and 3! respectively of the head 26 and of said bore, is a helical compression spring 32'. A pair of jam nuts 33, 34 threadedly engaging the protrudin rear end of the plunger stem 28 determine the extend of forward projection of the plunger 25 and also serve as a means for regulating the pressure of the spring 32.

From the foregoing, it will be readily understood that from the moment the end of the yarn carrier bar l strikes the plunger 25 as shown in Fig. III, its motion will be progressively retarded as said plunger recedes into the bore 27 and the resistance of the spring 32 increases, until it comes to rest against the head 21 of the abutment screw 20 as shown in Fig. IV. In this way the momentum of the rod is effectively checked before it is finally stopped, with assurance against rebounding and possible fouling of the needles or sinkers of the machine by the yarn carrier fingers on such rod. A knitting machine equipped with my improved end stops can accordingly be safely operated at higher speeds than ordinarily. It is to be noted that the'addition of the plunger 25 to the stop I! does not interfere with upward swinging of said stop to permit the. carrier rod to be slid beneath it to idle position as shown in dot and dash lines in Fig. III when its use is not required.

In the alternative form of end stop illustrated in Fig. VI, the abutment screw 20a is made hollow forpassage of the head of the plunger 25a axially through it, and is fixable in adjusted positions by. a set screw 24a which engages it laterally. The construction and operation of the alternative form of end stop is otherwise like that of Figs. III and IV. Accordingly in order to obviate the necessity for repetitive description the same reference'numerals have been employed to designate all other elements which have their counterparts in the first described embodiment, with addition in each instance however of the letter a for convenience of distinction.

In Fig. VII, I have shown my invention as embodied with a stop lug 35 aifixed to a reinforcing splice or plating thread carrier rod lb, with the abutment screw Zlb' and the yielding shock absorbing plunger 26b arranged to coact with a retractable intermediate or center stop lib.

As another variation of my invention, the lug 35 of Fig. VII may, if desired, be provided, in

lieu of the paralleling screw 20!) and plunger 261) with a combined stop abutment and shock absorbing means of the construction featured in Fig. V.

Having thus described my invention, I claim:

1. A yarn carrier rod stop for flat knitting machines, having associated therewith, an adjustable motion-limiting stop abutment, and a yielding shock-absorbing element which is axially spaced from the abutment and which normally projects forwardly beyond said abutment.

2. A pivoted yarn carrier rod end stop for use in connection with the narrowing nuts of flat knitting machines, having associated therewith, a yielding shock absorbing element which normally projects beyond the swinging end of the stop.

3. A retractable pivoted yarn carrier rod end stop for-use in connection with the narrowing nuts of flat knitting machines, having, at its swinging end, an adjustable motion-limiting stop, and a yielding shock-absorbing element which normally projects forwardly beyond said abutment.

4. A retractable pivoted yarn carrier end stop adapted for use in connection with the narrowing nuts of fiat knitting machines having, at its swinging end, an adjustable motion-limiting stop abutment, and a pring-backed shock-absorbing plunger which normally projects forwardly beyond said abutment.

5. A retractable pivoted yarn carrier end stop for use in connection with the narrowing nuts of flat knitting machines, having at its swinging end an adjustable motion-limiting stop abutment, a shock absorbing plunger confined to axial sliding in a bore adjacent the abutment, and normally projecting forwardly beyond the abutment, a spring backing the plunger, and means for regulating the pressure of the spring.

6. A retractable pivoted yarn carrier rod end stop for use in connection with the narrowing nuts of flat knitting machines, having associated therewith a combined motion-limiting stop abutment and shock-absorbing element in the form of a spring-pressed plunger which is confined to axial sliding movement within a bore in the stop, and which normally projects forwardly beyond the abutment, and means for limiting the inward movement of the plunger.

'7. A retractable pivoted yarn carrier rod end stop for use in connection with the narrowing nuts of flat knitting machines, having associated therewith a combined motion-limiting stop abutment and shock-absorbing element in the form of a plunger which is confined to axial sliding within a bore in the stop, and which normally projects forwardly beyond the stop, a spring backing the plunger, means for regulating the pressure of the spring, and means for limiting the inward movement of the plunger.

8. In yarn carrier rod stop means for flat knitting machines, an adjustable motion-limiting stop abutment, and a yielding shock absorbing element which is axially spaced from the abutment and which normally projects beyond said abutment.

9. In yarn carrier rod stop means according to claim 8,' in which the stop abutment and the shock absorbing element are both mounted on the carrier rod.

JOHN J. DOYLE. 

